Larus glaucoides
Status: Uncommon regular spring and fall migrant Lake McConaughy, Keith Co and Sutherland Reservoir, Lincoln Co, rare elsewhere. Uncommon regular winter visitor Lake McConaughy and Sutherland Reservoir, rare casual elsewhere.
Documentation: Description: 15 Jan 1907, Dorchester, Saline Co (Swenk 1907, Bray et al 1986).
Because of the existence of a cline from west to east (dark to light) in overall coloration encompassing forms assigned as “groups” to L. glaucoides by Chesser et al (2017), we consider it virtually impossible to assign most or all Nebraska records, especially of paler individuals, to the “groups” described by Chesser et al (2017). Thus, we cite above only the earliest documented Nebraska record that is clearly a representative of the cline.
Taxonomy: Formerly considered separate species in North America, Iceland Gull (L. glaucoides) and Thayer’s Gull (L. thayeri) were lumped into a single species L. glaucoides (Chesser et al 2017) with three subspecies, glaucoides, kumlieni, and thayeri. The decision to merge the two former taxa was based on non-assortative mating between them on Baffin and Southhampton Islands and questions about the validity of earlier research.
The status of “Kumlien’s Gull” is not well understood but the taxon was retained as a separate “group” by Chesser et al (2017). Although Snell et al (2020) showed that there is a complete unbroken cline in overall coloration from west to east, including even the easternmost and palest population of L. g. glaucoides in Greenland, Howell and Mactavish (2003) showed that kumlieni is clearly separable from thayeri, but reserved a conclusion on the relationship of kumlieni to glaucoides until variation in the latter has been investigated, a position taken as well by Howell and Dunn (2007). See Comments.
Through 2015 there were 10 documented spring reports, eight for fall, and 13 for winter of birds previously identified as Iceland (Kumlien’s) Gull as opposed to Thayer’s Gull, before the two were merged; these 31 records are described in Gubanyi (1996a, 1996b) and Brogie (1998, 1999, 2004, 2005, 2012, 2014, 2015, 2016). Since then, there have been two reports in spring 2018, one in Lancaster Co Dec 2020, and one in Scotts Bluff Co 23 Mar 2023 (eBird.org, accessed Oct 2023).
There are in all 11 records of birds reported as “glaucoides/kumlieni” 31 Dec-29 Mar, nine for Lake McConaughy, Keith Co and two for Branched Oak Lake, Lancaster Co. Only three birds have been reported as “thayeri/kumlieni“, singles at Branched Oak Lake 25 Nov-28 Dec 2020 and at Lake McConaughy 15 Feb 2018 and 20 Mar 2020 (eBird.org, accessed Oct 2023).
Spring: Feb 13, 13, 17 <<<>>> Apr 1, 1, 2 (away from Lake McConaughy and Sutherland Reservoir). See Winter for late winter dates at Lake McConaughy and Sutherland Reservoir.
Earlier dates away from Lake McConaughy and Sutherland Reservoir are 9 Feb 2015 Harlan Co, 9-16 Feb 2013 Lancaster Co, and 10-25 Feb 2024 (1-2) Branched Oak Lake, Lancaster Co.
Later dates away from Lake McConaughy and Sutherland Reservoir are 12 Apr 2018 Lancaster Co, 21 Apr 2020 Garden Co, and 29 Apr-2 May 2023 Lakes North and Babcock, Platte Co.
Fall: Nov 9, 10, 12 <<<>>> Dec 8, 10, 10 (away from Lake McConaughy and Sutherland Reservoir). See Winter for early winter dates at Lake McConaughy and Sutherland Reservoir.
Earlier dates away from Lake McConaughy and Sutherland Reservoir are of a first-year bird well-studied at Branched Oak Lake, Lancaster Co 1 Oct 2011, 3 Oct 2011 Lancaster Co, a first-year bird at Gavin’s Point Dam, Cedar Co 7 Oct-4 Dec 2018, 23 Oct 2020 Knox Co, 29 Oct-7 Nov 2019 Cedar Co, 30 Oct 2020 Douglas Co, 30 Oct-18 Nov 2021 Gavin’s Point Dam area, Cedar and Knox Cos, 2 Nov 2023 Lake Bennington, Douglas Co, 3 Nov 2023 Maloney Reservoir, Lincoln Co, 5 Nov 2019 Hall Co, and 7 Nov 2019 Cedar Co.
Later dates away from Lake McConaughy and Sutherland Reservoir are 13 Dec 2017 Harlan Co, 14 Dec 2023 Harlan County Reservoir, Harlan Co, 29 Nov-18 Dec 2010 Lincoln Co, 19-21 Dec 2020 Lancaster Co, 19-28 Dec 2020 Lancaster Co, 20 Dec 2022 Lancaster Co, 21 Dec 2021 Calamus Reservoir, Garfield Co, and 22 Dec 2023 Lake Maloney, Lincoln Co.
For later fall dates see Winter.
Adults often arrive in fall before immatures.
Winter: Nov 18, 19, 21 <<<>>> Apr 26, 29, 30 (Lake McConaughy and Sutherland Reservoir.) See below for winter dates away from Lake McConaughy and Sutherland Reservoir.
Earlier dates at Lake McConaughy and Sutherland Reservoir are 4 Oct 1997, 8 Oct 2019, 27 Oct 2022, 1 Nov 2010, 2 Nov 2020, and 14 Nov 2022.
Later dates at Lake McConaughy and Sutherland Reservoir are 3 May 2020, and 4 May 2022 Lake McConaughy, Keith Co, the latter a “beat to hell 1st-spring bird still with dark outer primaries” (Arthur, eBird.org).
The few mid-winter records away from Lake McConaughy and Sutherland Reservoir are 10 Dec 2023 Cedar Co, 14 Dec 2023 Harlan County Reservoir, Harlan Co, 10 Jan 2012 Lancaster Co, 22 Jan 2000 four Harlan County Reservoir, Harlan Co 22 Jan 2000 Johnson Lake, Gosper/Dawson Cos, 22-25 Jan 2012 (2-3 juveniles) Harlan Co Reservoir, 13 Dec-30 Jan 2015 Harlan Co Reservoir, 6-18 Feb 2013 Lancaster Co, 10-25 Feb 2024 Lancaster Co, 13-22 Feb 2023 Lancaster Co, and 25 Mar 2014 six Carter Lake, Douglas Co. Overwintering may occur on occasion at Harlan County Reservoir.
Recent reports at Lake McConaughy indicate that this species winters regularly, sometimes in numbers; most reports are of former Thayer’s Gull. Overwintering is unknown away from Lake McConaughy and Sutherland Reservoir, Lincoln Co; at the latter location, six were present 14 Jan 1998, five on 31 Dec 1998, and five on 29 Jan 2000.
In the period 6 Dec 1997-18 Apr 1998 at Lake McConaughy, age-class totals were 11 first basic, one third basic, and eight adults, for a total of 20 birds.
- High counts: (Lake McConaughy and Sutherland Reservoir) 15 at Lake McConaughy 4 Mar 1998, 14 (Thayer’s) at Lake McConaughy 18 Mar 2020, 14 (Thayer’s) there 9 Dec 2020, 11 there 14 Jan 2001, and 10 there 6 Feb 1999.
Comments: As with other large gull species, reports of former Thayer’s Gulls in Nebraska have dramatically increased since the 1990s. The increase can be attributed both to an increase in numbers present due to the number of ecologically mature reservoirs and the increasing amount of identification literature available. Former Thayer’s Gull was first reported in Nebraska in 1981 in Douglas-Sarpy Co 17-21 Mar without details (Cortelyou 1991), but not documented until 17-19 Dec 1992, the seventh report of the species, when Rosche described one at Sutherland Reservoir (Morris 1993). Most Nebraska records of Iceland Gull (sensu Chesser et al 2017) are of former Thayer’s Gull (thayeri), but there have been several reports of puzzling paler birds. There are no documented occurrences of the “glaucoides group” (sensu Chesser et al 2017) of Iceland Gull for Nebraska, although some photographed juveniles have been very pale. Most, however, are probably referable to kumlieni (sensu Howell and Mactavish 2003). Photographs of several of these birds are available at the Nebraska Ornithologists’ Union website.
There has arisen in recent years an additional problem of separation of paler Iceland Gull from the small Glaucous Gulls. This has been problematic on the Pacific Coast for some time, and has manifested itself at least once in Nebraska, where the identity of a bird at Branched Oak Lake 1-7 Dec 1996 was unresolved (Silcock and Jorgensen 1997). A very small (for Glaucous) white-winged gull at Lake McConaughy 9 Feb 2021 (Mlodinow, eBird.org) was initially thought to be a glaucoides Iceland Gull but bulky structure and field marks suggested Glaucous Gull. The identification as a small Glaucous Gull was confirmed by Louis Bevier and Bruce Mactavish. That this small Glaucous Gull might have been a representative of the small Glaucous Gull subspecies barrovianus, occurring mostly in the Bering Sea area and the Pacific Coast, was considered unlikely on geographic grounds; there are no confirmed Great Plains records of barrovianus.
Images
Literature Cited
Bray, T.E., B.K. Padelford, and W.R. Silcock. 1986. The birds of Nebraska: A critically evaluated list. Published by the authors, Bellevue, Nebraska, USA.
Brogie, M.A. 1998. 1997 (Ninth) Report of the NOU Records Committee. NBR 66: 147-159.
Brogie, M.A. 1999. 1998 (Tenth) Report of the NOU Records Committee. NBR 67: 141-152.
Brogie, M.A. 2004. 2003 (15th) Report of the NOU Records Committee. NBR 72: 59-65.
Brogie, M.A. 2005. 2004 (16th) Report of the NOU Records Committee. NBR 73: 78-84.
Brogie, M.A. 2012. 2011 (23rd) Report of the NOU Records Committee. NBR 80: 112-122.
Brogie, M.A. 2014. 2013 (25th) Report of the NOU Records Committee. NBR 82: 131-146.
Brogie, M.A. 2015. 2014 (26th) Report of the NOU Records Committee. NBR 83: 125-138.
Brogie, M.A. 2016. 2015 (27th) Report of the NOU Records Committee. NBR 84: 138-150.
Chesser, R.T., K.J. Burns, C. Cicero, J.L. Dunn, A.W. Kratter, I.J. Lovette, P.C. Rasmussen, J. V. Remsen, Jr., J.D. Rising, D.F. Stotz, and K. Winker. 2017. Fifty-eighth supplement to the American Ornithological Society’s Check-list of North American Birds. Auk 134: 751-773.
Cortelyou, R.G. 1981. 1981 (Fifty-sixth) Spring Migration and Occurrence Report. NBR 49: 38-55.
Gubanyi, J.G. 1996. 1992, 1993 (Fifth) Report of the NOU Records Committee. NBR 64: 30-35.
Gubanyi, J.G. 1996. 1995 (Seventh) Report of the NOU Records Committee. NBR 64: 132-138.
Howell, S.N.G., and B. Mactavish. 2003. Identification and variation of winter adult Kumlien’s Gulls. Alula 1: 2-15. http://www.gull-research.org/papers/papers4/Identification%20and%20Variation%20of%20Winter%20Adult%20Kumlien’s%20Gulls.pdf.
Howell, S.N.G., and J. Dunn. 2007. Gulls of the Americas. Houghton Mifflin Harcourt, New York, New York, USA.
Morris, R. 1993. Fall 1992 Occurrence Report (July 1 – December 31). NBR 61: 31-87.
Silcock, W.R., and J.G. Jorgensen. 1997. Winter Field Report, December 1996-February 1997. NBR 65: 17-27.
Snell, R.R., P. Pyle, and M.A. Patten. 2020. Iceland Gull (Larus glaucoides), version 1.0. In Birds of the World (P. G. Rodewald and B. K. Keeney, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.y00478.01.
Swenk, M.H. 1907. Two interesting Nebraska records. Auk 24: 223.
Recommended Citation
Silcock, W.R., and J.G. Jorgensen. 2024. Iceland Gull (Larus glaucoides). In Birds of Nebraska — Online. www.BirdsofNebraska.org
Birds of Nebraska – Online
Updated 10 Mar 2024